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534 Uppsatser om Soil mechanics - Sida 8 av 36
Betydelsen av kolkälla och mikrobiell fysiologisk status för temperaturresponsen (Q10) vid nedbrytning av organiskt material :
The increasing threat of climate change has led to a increased need for models to predict future climat. In these models the changes in the soil carbon pools due to changes in microbiel degradation of the organic matter can lead to both positive and negative feedback-effects. There is however a lack of consensues on the temperature respons on degradation soil organic matter. This paper aim to give a better understanding on the factors controlling the temperature respons. The factors studied were the carbon substrate qualitity and the physiological status of the microorganisms.
Torkat bioavfall som jordförbättringsmedel
The main project Dry preservation of source-separated organic household wastes involves a new technique for treatment of biowaste through drying. Investigations are going on to determine how the dried biowaste best can be used to close the natural circular flow of nutrients. The objective of this degree project is to determine if the dried biowaste can be used as a soil conditioner. By restoring the nutrients in the material to the ground, the natural circular flow is closed. A declaration of contents, including the nutrient levels, C/N ratio, pH and the electrical conductivity of the dried biowaste, was constructed and a germination test was done to make sure that the material did not inhibit sprouting.
Concentration and offtake of trace elements and macronutrients in Italian ryegrass (Lolium multiflorum Lam.) and spring barley (Hordeum vulgare L.) grown on soils amended with water treatment residual sludge
Aluminium sulphate (Al2(SO4)3) is usually added during the drinking water treatment processin order to precipitate organic and inorganic material, resulting in aluminium-based drinkingwater treatment residual sludge (WTR). Since 2003 Swedish law no longer permits WTR tobe deposited in lakes, and there is an interest to explore the possibility to utilize WTR as soilamendment. The aim of this study was to examine the effects of WTR application on cropgrowth and concentrations of macronutrients and trace elements (including micronutrients andpotential toxic elements). A greenhouse pot experiment was conducted with three soils; a clayloam rich in phosphorous (P), a loamy sand rich in P, and a silty loam with a low soil Pconcentration, and two crop species Italian ryegrass (Lolium multiflorum Lam. cv.
Kartering av markföroreningar inom Skutskärs Bruk samt utvärdering av spridningsrisker enligt Naturvårdsverkets MIFO fas 2
With the prospect of future construction on the Skutskär Pulp Mill property, Stora Enso Fine Paper has initiated an investigation of soil contaminants and a risk assessment of these contaminants. A soil and groundwater investigation has therefore been conducted on an open area of about 16 000 square meters, situated between the current wood room and digester house. To be able to integrate this study into an investigation for the whole industrial property, the study has been carried out as a phase 2 study according to the Swedish Environmental Protection Agency?s Methods of Inventories of Contaminated sites (MIFO).The site investigation has involved soil and groundwater sampling, together with the analysis of heavy metals and organic contaminants. The degree of hazard posed by the contaminants, the level of contamination, the potential for migration of the contaminants, as well as the degree to which protection of human health and the environment is required in the area, have been weighed together for an overall risk assessment of the area with regard to human health and the environment.The investigated area was built up by filling in the coastal waters.
Hygienisering av torkat bioavfall
The main project Dry preservation of food waste from households includes a new technique concerning drying and storage of dried biowaste as well as a study of the sorting of household waste and further usage of the dried biowaste. A question asked in the project is, can the dried biowaste be used as a soil amendment? If organic waste is used as a soil amendment, precaution concerning hygienic safety risks has to be accounted for. The objective of this M. Sc.
Side effects of biological control agents in agriculture : does the bacteria Bacillus amyloliquefaciens affect the earthworm Aporrectodea longa?
Pathogenic microorganisms pose a big threat towards food production. Meanwhile, negative impacts on humans and environment are seen by the use of pesticides. Biological control agents are an alternative to the use of chemical pesticides, and plant-growth promoting rhizobacteria, such as Bacillus amyloliquefaciens has been shown to have good properties as biocontrol agents. Before these bacteria can be used commercially their impact on other soil organisms has to be evaluated. This thesis looks into what biocontrol bacteria are and how they might affect earthworms.
Smörjning Av Lager
The work thesis was performed at Assalub a company which is situated in Åtvidaberg. The company works with developing, manufacturing and marketing equipment for handling of lubricants for light and heavier industry. The work thesis it is based on a inquiry Assalub got from MacGregor which is a company within cargo solution, from port to offshore system.For unloading grain and other material from the ship cargo it is used combined inlet feeder and screw conveyor, there the inlet feeder is drilling down through the cargo and feed the screw conveyer with material to further destination. At the bottom of the screw conveyer and the inlet feeder there is a bearing that keep the parts together. However the lubrication of the bearing must be made manually.
Reducerad jordbearbetning : en fallstudie
This is a study made because I would like to see how much money can be saved when
reduced soil preparations is used. This is a case study, the farm is located in the north
vest part of Skåne, Sweden.
I have calculated with four different soilpreparation methods.
Alternative 1: Conventional soil preparation, the way the farm is managed today.
Alternative 2: Ploughing on depth of 12 centimeters, with a ridge packer followed with
sowing.
Alternative 3: Eco-tillage
Alternative 4: Direct drilling
The results of my study showes that Alternative 2 is the most profitable. Alternative 4 is
very good if you see to dieselexpenses and hours of work, but the yield is far to low.
If the numbers are further analized, it showes that in spring barley the differense
between Alternative 2 and Alternative 4 is at a minimum. So if there is lack of time for
one reason or another, this might be an alternative in spring barley.
The differense in how the farm is managed today and the most profitable alternative in
the study, Alternative 2 showes that it can be saved up to 60 940 SEK..
Markvattenhalt och temperatur i sandig jordbruksmark vid Ilstorp, centrala Skåne : en mätnings- och modelleringsstudie
Vinderosion på jordbruksmark har länge varit ett välkänt faktum trots att någon utförligare undersökning om dess omfattning och skadeverkan inte tidigare genomförts. Mot bakgrund av detta har därför ett nordeuropeiskt projekt, WEELS (Wind Erosion on European Light Soils), dragits i gång som syftar till kartlägga vinderosionen på sandig jordbruksmark i norra Europa och som man i slutändan hoppas ska kunna resultera i en vinderosionsmodell. Detta har genomförts med SOIL modellen, en matematiskt fysikaliskt baserad modell för simulering av vatten och värmeflöde i en skiktad jordmånsprofil..
Demand and perception of fertilizer : among small-holder farmers in Kenya
Hunger is a problem in some parts of the world (www, FAO 1, 2012). The lack of food is often a result of insufficient knowledge in soil fertility management (Röing de Nowina, 2012). Ongoing hunger and malnourishment are quite prevalent in Sub-Saharan Africa and are often combined with poverty (www, FAO 1, 2012). Farming is the most common occupation in this area and the farms are often small-scale farms with subsistence crops and a few cattle. The farmers who operate these small-scale farms are economically a weak group.
Hur påverkasogräsuppkomsten av jordbearbetning :
Today it is common to spray against most weeds by using very expensive weed-killers.
The goal for every farmer is to have as low costs as possible for their use of machines and weed-killers.
Therefore it is in everyones interest to find other methods to fight the weeds.
Finding a way to reduce the rise and growth of weeds already at the preparation of the soil would lower the number of laps over the field and also decrease the amount of weed-killing dose.
Tests show that by harrow in the dark it is possible to reduce the population of weeds with up to 60%, but the normal reduction would be about 20-30%.
To verify the results above we made tests by using two different methods of preparing the soil. We tested ploughing and harrowing in daylight and during night. Later we checked the number of different weeds in areas prepared in daylight and during night.
By studying the results from the different methods used we found a considerable reduction of some kinds of weeds in areas prepared during night..
Den bäcknära zonen vid små skogliga vattendrag i Värmland : generell beskrivning, förekomst av traktorspår samt kvicksilverhalter i körpåverkat ytvatten
Forest streams and the associated riparian zones are sensitive to disturbances and changes that occur within these riparian areas. Particularly sensitive are small streams of low order, which will have large impacts down-stream. The disturbances that occur in the riparian zones are reflected quickly in the stream. Driving with forestry machines in the riparian zone will have detrimental effects to the soil and water. Driving the machines will lead to changes in the mineral soil composition, resulting in the reduction of porosity, less infiltration, compaction, and an increased bulk density.
Preparatanvändning och ogräsförekomst på gårdar med olika jordbearbetningsstrategier
Reduced tillage has increased in Sweden during several years, primarily to decrease costs andincrease efficiency in crop production. Despite this, mouldboard ploughing is still the mostcommon primary tillage method on most farms. The aim with this thesis was to compare theuse of pesticides and the occurrence of weeds on ten farms in Skåne and ten farms inMälardalen that use different soil tillage systems. The object of the study was also to clarifywhy the farms had chosen their specific soil tillage system and the consequences it has had onweed occurrence and use of pesticides. The result showed a slightly higher use of pesticideson the farms that use reduced tillage.
Inventering av förorenade områden enligt MIFO-fas 1 : Erasteel Kloster AB, Söderfors
Erasteel Kloster AB Söderfors have been commissioned by the county administrative board in
Uppsala län to make an inventory of possible contaminations in theirs industrial- and landfill areas on the basis of the Swedish Environmental Protection Agency?s; ?Method of Surveying Contaminated Sites-phase 1? (MIFO-fas 1). The inventory starts with maps and archive studies, place visits and interviews, and finally a risk classification is done. A risk classification is a compilation of four categories; pollutant toxicity, contamination level, possible spreading condition of the pollutant, sensitivity and protection value of the environment.
In this paper five partial areas (Holmen- and Jörsöområdet, Järnsvampsområdet,
Ingsådeponin, Östra verken and Myrområdet) have been described from a historical point of
view. Only parts of four areas have been risk classified (Holmen- and Jörsöområdet,
Järnsvampsområdet, Ingsådeponin and Östra verken), due to that the other areas isn?t own by Erasteel Kloster AB.
Holmen- and Jörsöområdet
Holmen- and Jörsöområdet have during the entire activity time been carried out as the
production core in the company.
Phosphorus in agricultural soils around the Baltic Sea : comparisons of different laboratory methods as indices for phosphorus leaching to waters
Eutrophication of the Baltic Sea is a serious problem. A major contributing factor is diffuse losses of phosphorus (P) from agricultural land in surrounding countries. In order to estimate P losses, environmental monitoring of small agriculture-dominated catchments is being carried out in most of these countries. Evaluation of the risk of P leaching to waters is usually based on chemical tests originally developed to quantify the amount of soil P available for plant production. The tests are performed in different ways in the different countries and a number of different extraction agents are in use.